When doctors speak of precancer of the skin, they are usually speaking about actinic keratosis, which is the main precancer leading to squamous-cell carcinoma. Again, there is no known precancer for basal-cell carcinoma; the author and most academic, university-based dermatologists and dermatologic surgeons believe it is best not to consider moles as precancer to melanoma. So, in a nutshell, the only precancer that counts is that leading to squamous-cell carcinoma, a potentially deadly tumor. Please remember that a TRUE precancers will not kill or harm patients RIGHT NOW, so do not be misled by material that contradicts this statement. But that does not mean that a given precancer cannot turn into a deadly cancer in the future.

Precancers usually require treatment only because they MAY become cancers, or because they are unsightly or crust or do not heal. Only about 5% or 1 in 20 actinic keratoses (precancers) will become squamous-cell cancer. Since it may be difficult to predict which precancer will turn into cancer, doctors usually do their best to treat as many precancers as possible in order to reduce the chance that one will become malignant. All treatments for precancers (actinic keratoses) have their limitations. In this section, we will look at the more-established, traditional treatments. "Newer" (that does not always mean better) treatments for skin precancer and skin cancer can be found in the website subsection Future Treatments. A brief table will be presented to compare the risks and benefits. After all, it is this balance, carefully weighed in each individual case, that helps to determine which treatment is the best. Let us first talk of some of the limitations of traditional treatments.

Scraping and burning (curettage and desiccation) usually results in sores that may take weeks to heal, with significant potential to scar. Scraping and burning may be done lightly or deeply. The deeper the treatment, usually the higher the cure rate, but the longer the wound takes to heal and the greater the chance that the final result will be a white, porcelain-like scar. To restate more simply a doctor who gives you a higher cure chance usually will scar and disfigure you more with this very traditional treatment. Doctors should make patients aware that scars can result from the scraping-and-burning type of treatment, especially if the treatments are on the face. Scraping and burning is also known as C&D by most skin professionals.

Dermabrasion is the sanding of skin by hand or electric sanding wheel and can be used to treat many degrees of precancer. It is highly successful when performed by the most-skilled doctors. Scarring rarely results but the same principles usually apply as just described for "scraping and burning." Unfortunately, the freezing solution used to freeze the skin just prior to dermabrasion, Freon™, is no longer available for this purpose. Dermabrasion, a great tool, may now be a dying art through no fault of its own.

Precancer treatment with fluorouracil (5-FU, Efudex, Floroplex) is best carried out, and was studied for FDA (United States Food and Drug Administration) approval, with two to four weeks of twice daily treatment per the Physicians Desk Reference or PDR. Fluorouracil has been used by dermatologists to treat precancers for over 25 years. In that time, dermatologists have learned a good deal about using 5-FU. The author trained under a number of world-famous academic dermatologists at three of the top ten programs in the world. These famous teaching dermatologists felt that six weeks of 5-FU was necessary for proper treatment. Unfortunately, the fluorouracil treatment schedule, even with steroid creams to quench the burning and pain caused by the fluorouracil, has been modified by many treating doctors, including dermatologists, to periods of two weeks or less. This "undertreatment" is done to avoid the severe reactions and possible scarring that naturally comes with destroying all of the precancerous cells with fluorouracil in a large area. Over the years, after watching numerous modifications (by other doctors) of the original approach to using 5-FU fail to live up to the original recommendations for use, the author respects even more the ideas of his teachers/professors. Failures for 5-FU treatment are not just the return of precancers but include: the apparent clearing of the surface skin by the 5-FU treatment while precancer cells transform into cancer cells deeply (especially in the deep hair pores of the scalp) then spread spread locally into the surrounding tissues and then unfortunately often spread inside a patient (metastasize) causing death.

What is the downside of 5-FU? 5-FU works by interfering with the DNA & RNA or genes of cells. It usually has a greater effect on the the genes of more rapidly dividing cells (cancers and precancers). The effect on the genes is somewhat similar to the effects of a "bad mutation". The trouble is that 5-FU is absorbed through the skin into the bloodstream and body and that all cells in the body may have their genetic material "changed" and not for the best by the drug. In the Efudex preparation that number is about 6% of the total applied dose. Unfortunately, this was only recently made obvious to the public in the package insert after so many years of being on the market. The website author certainly is concerned about bathing liver, and lung and bowel and pancreas cells in 5-FU. After all, there exist no good studies for such a widely used medication as 5-FU in which patients are followed for 10 or 20 years to see if they have a 3 or 5 or 10% greater chance of internal cancer after single or multiple uses of 5-FU containing skin treatments. Also most unfortunately, many doctors are still giving 5-FU containing creams to women of child bearing age, 15-45 years usually, for the treatment of actinic cheilitis or precancer of the lips. The package insert now warns such women of potential "birth defects."

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When considering the following paragraphs please be aware that the website author feels that all treatments should be offered as options to a patient, and that 5-FU is an important and useful drug. However, 5-FU does have some problems; none of which should be understated to the patient who should be given a choice of treatments for precancers. For example, the PDR cites 5-FU as having the risks of scarring and infection. The website author has seen many patients who had been given 5-FU by other doctors and who had both infection and scarring. The website author has seen particularly severe reactions in patients who have underlying skin diseases such as rosacea and seborrheic dermatitis who have received 5-FU containing skin treatments from other doctors. Scarring and infection following treatment with 5-FU is not uncommon. It is important to both patients and medical science that precancers and the possibly deadly squamous-cell cancers they form should be treated as effectively as possible. If the way 5-FU is going to be used (how often, how long) on patients is changed then it is important that properly performed scientific studies support the changes. Many patients' lives will depend upon true and untainted studies.

State and Federal Medicare officials make decisions on paying for different types of medical treatment that depend upon what they read and hear. A patient that is not on Medicare may be effected since many other insurance companies copy and use Medicare's guidelines and visa versa. Sometimes Medicare decisions (guidelines) may be political as once seen with a past mandate on 5-FU. The decisions were successfully undone after many years of painful, non-covered and expensive treatments on elderly Medicare patients, thousands of lobbying hours by dermatologists and other medical specialists with the help of AARP. By clicking on the small icon below, you may read (requires approximately 5 minutes) how politics may affect insurance coverage of precancers.

To restate, under-treating actinic keratoses with any method, including fluorouracil, can result in a normal-appearing surface skin while the abnormal precancer cells grow and mutate into cancer cells below, in a hair pore, for example. Deeper "missed" precancer cells can have the potential to turn into deep squamous-cell cancer which can go into the blood or lymph stream, spread to other parts of the body and be fatal. Driving precancers deep with fluorouracil is not an uncommon event, as the late, well-respected skin-cancer surgeon Dr. Henry Menn of the University of Miami frequently noted when addressing medical meetings. Dr. Menn stated that inappropriate [under]treatment with fluorouracil on the face and scalp caused the death and serious disease of many patients that were sent to him in consultation "too late."

We must put inappropriate fluorouracil treatment into proper context. Many patients with moderate to severe actinic keratoses have one hundred or more actinic keratoses on the face and scalp. If we assume that inappropriately short fluorouracil treatment is performed, and that undertreatment permits a deep, possibly fatal, squamous cancer in one patient in ten over a lifetime, then we can estimate that the inappropriate fluorouracil missed 1 in 1,000 precancers or has a 99.9% cure rate. However, inappropriately [under]applied fluorouracil may likely be even less effective than this, depending upon the thickness of the precancers treated. The thicker the precancers, the more the patient needs the full six weeks of treatment, because it is likely that the precancers are growing down as well as up. Fortunately, the body helps "clear" a great percentage of damaging or irritating precancers on its own.

The author does not believe that fluorouracil should be used by most patients for "spot" treatments. Imagine that a target precancer, the width of a pencil eraser, is located about an inch above the patient's nose. If the patient correctly applies the fluorouracil cream for one week, the spot will start to fade. But what if in the second week of treatment, the patient incorrectly applies the cream as little as one-half inch off target? The patient may then be unaware because the target may have started to fade and normal skin usually has no reaction to fluorouracil. In that case, the precancer will be under-treated just as if the patient had used fluorouracil for too few days. In some more serious cases like that of an infiltrating basal-cell cancer, which might look like a precancer to the untrained eye, the patient may obscure the cancer with "spot" treatment. Here again, inadequate treatment of the target location may cause the surface of the cancer to fade initially. However, the cancer may then be left to grow deeper into the skin and leave an untreated infiltrating basal-cell cancer that can not be seen from the surface.

Fluorouracil can be a useful medicine if used properly and on the right patients. If the author recommends fluorouracil to his patients, he wants them covering an entire area like the face or arm or scalp for the appropriate time. In Florida the heat and sun causes patients to react more severely to six weeks of fluorouracil, as well as to develop staphylococcus infections of the eroded skin (Impetigo), we cautiously recommend the medicine and allow our patients to refuse the treatment. Using the medicine during the cooler months and winter up north is helpful sometimes. This is especially true with patients who have sensitive skin and other sensitive skin diseases such as rosacea and seborrheic dermatitis .

The author tends to favor the use of liquid nitrogen freezes in many precancer cases. In skilled hands and in the hands of a dermatologist who is extremely nearsighted or one who uses magnification constantly, the odds of scarring are low and the numbers of lesions cured is very good. There is, however, a chance of depigmenting (permanently lightening) the skin, depending upon the depth of the precancer treated and the location on the body and the quality/type of skin treated. A benefit of liquid nitrogen is that most precancers frozen with liquid nitrogen heal within a week. If it takes much longer to heal, that may be a or hint that the precancer is deeper than can be seen with the naked eye, is made of more abnormal cells or may be an entirely different cancer altogether. The hint could arouse the patient or surgeon to biopsy the area and test the biopsy in the lab, leading to the discovery of a cancer, which can then be treated properly.

A simplified way to look at liquid nitrogen (LN2) treatment for precancers is as follows. The LN2 kills both precancer and normal cells on the surface skin very quickly during the thawing phase. The cells necessary to replace the deliberately damaged surface skin lie deep in the adjacent hair pores. The face and scalp have the some of the highest hair pore (that does not mean hair!) counts on the body. A good portion of normal cells live or make up the hair pore, unfortunately, near or underlying a precancer many precancer or abnormal cells live in the hair pore. Following the damaging surface treatment cells divide in the hair pore. Good cells win the race to replace the surface 80% of the time and bad or precancer cells 20% of the time. Unfortunately, deep LN2 treatment can kill precancers 100% of the time by destroying the entire hair pore, this unfortunately usually results in 100% white scar marks. Very few patients would like that outcome. Over-treatment of precancers is often a cause of patient dissatisfaction with their doctor.

The author prefers to give the following choice to his patients: "A liquid nitrogen freeze will likely kill 80% of precancers, leaving 20% which may return. With this level of freezing, there will usually be no scarring and you will heal within one week. The alternative is to freeze to kill 100% of precancers. However, at least 10% of people will scar. You will heal in two weeks. Which type of freeze you would like? It is easy to treat the remaining or returning precancers at a later date during a routine follow-up visit."

 

The author believes that cutting and sewing is rarely justified in treating precancers. By definition, precancers are surface (on the top of the skin) growths. Deep treatment like cutting and sewing violate the deepest dermis, well below the base of the hair pores and glands where precancers do not even grow, and the definite resulting scarring would be acceptable only if the precancer kept returning after trying various or multiple other treatments. Certain precancers might return if there is significant precancer cell growth down the edges of hair follicles (pores). Cells might remain hidden from the doctor using more traditional treatments because most precancer treatments are fairly superficial. Insurance companies usually pay the doctor more money for cutting and sewing than for other treatments. This can also become an issue. For example, cases exist of Board Certified Plastic Surgeons cutting out precancers with $1,000 flaps of skin while billing patients and insurance carriers for what might have been successfully treated without scarring for $7.00 by a dermatologist.

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